Without interpreters, we wouldn’t have software, but yet interpreters are also software. This is why we talk about `bootstrapping’, where software pulls itself from the floor by its bootstraps, a paradox settled by the existence of hardware microcode.
Any piece of software exists as a combination of two parts, some instructions in a computer language and an interpreter of that language. Alone they do nothing, put them together and they can notionally do anything. Often there are intermediary steps, commonly interpretation into another language called `bytecode’ to produce `binaries’, but these are just translations into another language, which still needs interpreting for the magic to happen.
Interpreters are fantastic, they allow us to try out ideas beyond our imaginations, adding some instructions, interpreting them to get output rendered as sound or light to our senses, perceiving otherwise impossible worlds, and returning to the source code to twist the encoded structures into new contortions inspired by the results so far. We humans expand the realms of perception through computation, not creating things but writing about things in order to magic them into existence. We’re only scratching the surface of what’s possible, artistic and otherwise, from marrying high speed computation with embodied human experience.
It’s a shame then that the freedom of thought that interpreters give us happen to threaten business models of large companies, who are accordingly searching for the power to make free access to them them illegal. `Console’ computers (a misnomer if I ever saw one) are those where the end user is not allowed access to an interpreter, without paying for a restrictive license and/or expensive hardware. You are not allowed to modify code, certainly not allowed to modify the interpreter, and so must be satisfied with using whatever programs the manufacturer allows you to.
What is frightening is that these business models are spreading — from computer games, to handheld computers and now to tablets. The iPhone (and now iPad) was a particular shock as a device from a company producing hardware traditionally marketed at the creative. You certainly can be creative with an iPad, but only using a surface level interface; you can touch the screen to make a mark, but you can’t write a program about touch, or about marks. iScratch, a project that allowed children to interpret their programs on the iPhone, has been rejected from the apple store. Such interpreters have been banned from the iPhone from the start (apart from the concession of a javascript web browser VM without access to, for example, sound synthesis), but a big media stir has only been made since interpretation was locked down on the development side too, having impacts on some crappy tools by a large company.
This creep towards centralised control over interpretation is deeply worrying, and arguments that end-users get confused or threatened by higher order thought are frankly sinister. Can we have our languages back, please?
UPDATE: If you needed convincing on the point of interpreters allowing higher order creativity, check out Dave’s latest work: http://www.pawfal.org/dave/blog/2010/04/lazybotz/
